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Field experiments were conducted to test the influence of two types of anionic polyacrylamide ( PAM) on soil erosion and runoff of sloping land in Jordan under natural rainfall conditions. The two PAMs used in this study, Superfloc A- 836 and Superfloc A- 870, varied widely in molecular weight ranging qualitatively from high, 15Mg/mol, to very low and surface charge from 20% to 70%, respectively. Fourteen 2- m x 10- m field plots with a 12% slope gradient were constructed in the field. Collection barrels were installed at the end of plots to monitor the amount of runoff and sediment loss after each storm. The PAMs were applied at two rates of 10 and 30 kg/ ha plus a control. The experimental design includes seven treatments with two replicates. Experimental results showed that PAM was effective in reducing runoff and soil loss at the two application rates. Application of A- 836 reduced runoff and sediment loss by 23% and 35%, respectively, compared to control and the corresponding average decrease in runoff and soil loss for A- 870 were 16% and 8%, respectively. Differences in runoff among PAM- treated plots at 10 and 30 kg/ ha were negligible, but soil loss was slightly lower in the 30 kg/ ha PAM- treated plots. Polyacrylamide application increased dry matter crop yield, and the application rate seemed to have a greater influence than the PAM type. The average dry matter yield for both PAMs at 30 kg/ ha and 10 kg/ ha increased by 56% and 35%, respectively, compared to control.